Lockheed Martin paid $5 million to settle whistleblower allegations the company mishandled nuclear waste at the Paducah Gaseous Diffusion Plant near Paducah, Ky., a uranium enrichment facility the company once operated for the U.S. government for about 15 years, the Department of Justice said Monday.

The government’s lawsuit alleged Lockheed Martin violated a key 1976 law about hazardous waste management “by failing to identify and report hazardous waste produced and stored at the facility, and failing to properly handle and dispose of the waste,” according to a DOJ a press release. Lockheed then falsely claimed it had adhered to the law and claimed payment for the waste-handling work under its contract with the Energy Department, the Justice Department said.

Lockheed Martin heritage companies operated the Paducah Gaseous Diffusion Plant under contracts with the Department of Energy and the government-owned U.S. Enrichment Corp. — now the private company Centrus Energy — from 1984 to 1999.

The whistleblower case was filed in the U.S. District Court for the Western District of Kentucky on 1999 under the False Claims Act by former Lockheed employees and a Washington-based nonprofit, the Natural Resources Defense Council. In false claims cases, whistleblowers may file on the government’s behalf, and the government may later join the case. The U.S. attorney for Western Kentucky did so in 2003.

The former Lockheed employees who blew the whistle will receive $920,000 of the $5 million settlement, in which Lockheed admitted no wrongdoing, the Justice Department said.

In a 10-K report filed Wednesday with the Securities and Exchange Commission, Lockheed said it is settling the case to prevent additional legal expense but does not admit liability or misconduct.